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Jog 35 5.Pdf GemmologyThe Journal of Volume 35 / No. 5 / 2017 The Gemmological Association of Great Britain Contents GemmologyThe Journal of Volume 35 / No. 5 / 2017 COLUMNS p.386 373 What’s New Multi-colour-temperature lamp|PL-Inspector|AGTA report on Myanmar|ASEAN Gem & p. 388 Jewelry Review|Atypical pearl culturing in P. maxima|Conflict diamonds and Cameroon| Diamond origin identification using fluorescence|Global Diamond Industry 2016|ICGL Klaus Schollenbruch photo Newsletter|Japanese journal online|Raman spectrometer sensitivity|Gold demand trends 2016|Agate Expo DVDs|AGTA ARTICLES 2017 Tucson seminars|Color- Jeff Scovil photo Codex colour referencing system| Feature Articles GemeSquare and MyGem- ewizard apps|Gemewizard 404 Synthetic Emeralds Grown by W. Zerfass: Historical monitor calibration kit|Fabergé Account, Growth Technology, and Properties online|Reopening of The Lap- By Karl Schmetzer, H. Albert Gilg and Elisabeth Vaupel worth Museum of Geology 378 Practical Gemmology 416 Rethinking Lab Reports for the Geographical Moonstone mystery Origin of Gems By Jack M. Ogden 380 Gem Notes Red beryl matrix cabochons| Gemmological Briefs Ceruleite from Chile|Yellow danburite from Namalulu, 424 Fake Pearls Made from Tridacna gigas Shells Tanzania|Emerald from By Michael S. Krzemnicki and Laurent E. Cartier Ethiopia|Vivid purplish pink fluorite from Illinois, USA| 430 Large 12-Rayed Black Star Sapphire from Sri Lanka Colourless forsterite from with Asterism Caused by Ilmenite Inclusions Vietnam|Sapphire from By Thanh Nhan Bui, Pascal Entremont and Jean-Pierre Gauthier Ambatondrazaka, Madagascar| Colour-change scorodite from 436 Tsumeb, Namibia|Stichtite| Excursions Zoned type IaB/IIa diamond| Mogok, Myanmar: November 2016 Synthetic star ruby 444 Conferences AGA Tucson|GIT|Jewelry Industry Summit Cover Photo: High-quality rubies, sapphires 450 Letters and emeralds are typically ac- companied by geographical origin reports from gemmologi- 451 Gem-A Notices cal laboratories, as discussed on pp. 416–423 of this issue. Shown in this composite photo are 452 Learning Opportunities matched pairs of Colombian em- eralds, Kashmir sapphires and Burmese rubies (total weights 457 New Media approximately 10, 7 and 4 ct, re- spectively). Courtesy of Joseph Ambalu, Amba Gem Corp., New York, New York, USA. 460 Literature of Interest The Journal is published by Gem-A in collaboration with SSEF and with the support of AGL and GIT. ISSN: 1355-4565, http://dx/doi.org/10.15506/JoG.2017.35.5 i The Journal of emmology G THE GEMMOLOGICAL ASSOCIATION OF GREAT BRITAIN Editor-in-Chief Production Editor Marketing Consultant Brendan M. Laurs Mary A. Burland Ya’akov Almor [email protected] [email protected] [email protected] 21 Ely Place Editorial Assistant Editor Emeritus Executive Editor London EC1N 6TD Carol M. Stockton Roger R. Harding Alan D. Hart UK Associate Editors t: +44 (0)20 7404 3334 Ahmadjan Abduriyim, Tokyo, Japan; Raquel Alonso-Perez, Harvard University, Cambridge, f: +44 (0)20 7404 8843 Massachusetts, USA; Edward Boehm, RareSource, Chattanooga, Tennessee, USA; Maggie e: [email protected] Campbell Pedersen, Organic Gems, London; Alan T. Collins, King’s College London; John w: www.gem-a.com L. Emmett, Crystal Chemistry, Brush Prairie, Washington, USA; Emmanuel Fritsch, University of Nantes, France; Rui Galopim de Carvalho, Portugal Gemas, Lisbon, Portugal; Lee Registered Charity No. 1109555 A. Groat, University of British Columbia, Vancouver, Canada; Thomas Hainschwang, GGTL A company limited by guarantee and Laboratories, Balzers, Liechtenstein; Henry A. Hänni, GemExpert, Basel, Switzerland; Jeff registered in England No. 1945780 W. Harris, University of Glasgow; Alan D. Hart, Gem-A, London; Ulrich Henn, German Registered office: Palladium House, Gemmological Association, Idar-Oberstein; Jaroslav Hyršl, Prague, Czech Republic; Brian 1–4 Argyll Street, London W1F 7LD Jackson, National Museums Scotland, Edinburgh; Stefanos Karampelas, GRS Gemresearch Swisslab, Basel, Switzerland; Lore Kiefert, Gübelin Gem Lab Ltd., Lucerne, Switzerland; Hiroshi Kitawaki, Central Gem Laboratory, Tokyo, Japan; Michael S. Krzemnicki, Swiss Gemmological Institute SSEF, Basel; Shane F. McClure, Gemological Institute of America, Carlsbad, California; Jack M. Ogden, Striptwist Ltd., London; Federico Pezzotta, Natural President History Museum of Milan, Italy; Jeffrey E. Post, Smithsonian Institution, Washington DC, Maggie Campbell Pedersen USA; Andrew H. Rankin, Kingston University, Surrey; George R. Rossman, California Institute of Technology, Pasadena, USA; Karl Schmetzer, Petershausen, Germany; Dietmar Schwarz, Vice Presidents Federated International GemLab, Bangkok, Thailand; Menahem Sevdermish, Gemewizard David J. Callaghan Ltd., Ramat Gan, Israel; Guanghai Shi, China University of Geosciences, Beijing; James Alan T. Collins E. Shigley, Gemological Institute of America, Carlsbad, California; Christopher P. Smith, Noel W. Deeks American Gemological Laboratories Inc., New York, New York; Evelyne Stern, London; E. Alan Jobbins Elisabeth Strack, Gemmologisches Institut Hamburg, Germany; Tay Thye Sun, Far East Andrew H. Rankin Gemological Laboratory, Singapore; Pornsawat Wathanakul, Gem and Jewelry Institute of Thailand, Bangkok; Chris M. Welbourn, Reading, Berkshire; Bert Willems, Leica Microsystems, Honorary Fellows Wetzlar, Germany; Bear Williams, Stone Group Laboratories LLC, Jefferson City, Missouri, USA; Gaetano Cavalieri J.C. (Hanco) Zwaan, National Museum of Natural History ‘Naturalis’, Leiden, The Netherlands. Terrence S. Coldham Emmanuel Fritsch Content Submission The Editor-in-Chief is glad to consider original articles, news items, conference/excursion Honorary Diamond Member reports, announcements and calendar entries on subjects of gemmological interest for Martin Rapaport publication in The Journal of Gemmology. A guide to the various sections and the preparation of manuscripts is given at www.gem-a.com/index.php/news-publications/publications/ Chief Executive Officer journal-of-gemmology/submissions, or contact the Production Editor. Alan D. Hart Subscriptions Gem-A members receive The Journal as part of their membership package, full details Council of which are given at www.gem-a.com/membership. Laboratories, libraries, museums and Justine L. Carmody – Chair similar institutions may become Direct Subscribers to The Journal. Kathryn L. Bonanno Paul F. Greer Advertising Kerry H. Gregory Enquiries about advertising in The Journal should be directed to the Marketing Consultant. J. Alan W. Hodgkinson For more information, see www.gem-a.com/index.php/news-publications/publications/ Nigel B. Israel journal-of-gemmology/advertising. Jack M. Ogden Richard M. Slater Database Coverage Christopher P. Smith The Journal of Gemmology is covered by the following abstracting and indexing services: Australian Research Council academic journal list, British Library Document Supply Branch Chairmen Service, Chemical Abstracts (CA Plus), Copyright Clearance Center’s RightFind Midlands – Georgina E. Kettle application, CrossRef, EBSCO (Academic Search International, Discovery North East – Mark W. Houghton Service and TOC Premier), Gale/Cengage Learning Academic OneFile, GeoRef, South East – Veronica Wetten Mineralogical Abstracts, ProQuest, Scopus and the Thomson Reuters’ Emerging South West – Richard M. Slater Sources Citation Index (in the Web of Science). Copyright and Reprint Permission For full details of copyright and reprint permission contact the Editor-in-Chief. The Journal of Gemmology is published quarterly by Gem-A, The Gemmological Association of Great Britain. Any opinions expressed in The Journal are understood to be the views of the contributors and not necessarily of the publisher. Printed by DG3 (Europe) Ltd. © 2017 The Gemmological Association of Great Britain Understanding Gems ™ Cert no. TT-COC-002454 ISSN: 1355-4565 ii The Journal of Gemmology, 35(5), 2017 What’s New INSTRUMENTATION Multi-Colour-Temperature Lamp PL-Inspector The Gem-A Shop is now carrying a Gemetrix Pty Ltd released its multi-colour-temperature lamp that new PL-Inspector instrument in can be used for diamond grading, observ- May 2016 at the Mediterranean ing colour change, and as an ambient light Gem and Jewellery Conference in source. The 3,700–3,900 K setting is espe- Spain. It contains a portable UV cially useful for viewing jade and emerald, light source, weighing only 300 4,200–4,500 K is suitable for ob- g, that provides both short-wave serving most coloured stones and (255 nm) and long-wave (365 5,000–5,500 K is ideal nm) radiation for the observation for diamonds and blue of fluorescence and phosphores- sapphires. The lamp has cence in gems (particularly dia- eight levels of brightness mond). An optional battery pack makes the unit suita- controlled by a touch-sensitive slide. The flex- ble for travel. Visit http://gemetrix.thediamondpages. ible head folds for storage. The unit comes with a com/PLinspector.html; for North American orders, go 100/240 V adaptor and a USB-powered connector. to www.gemconference.com/store and for European To order, email [email protected]. CMS orders visit www.iglcert.gr. CMS NEWS AND PUBLICATIONS AGTA Report on Myanmar Gem Sector Southeast Asian Nations In October 2016, the American (ASEAN) focuses on the col- Gem Trade Association led a oured stone trade between visit to Myanmar that included Thailand and Myanmar, e- a delegation of American gem commerce opportunities in industry representatives. In Thailand and ASEAN, the January
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